U.S. patent number 8,488,436 [Application Number 13/365,408] was granted by the patent office on 2013-07-16 for high density data storage medium, method and device.
This patent grant is currently assigned to International Business Machines Corporation. The grantee listed for this patent is Richard Anthony DiPietro, Urs T. Duerig, Jane Elizabeth Frommer, Bernd Walter Gotsmann, Erik Christopher Hagberg, James Lupton Hedrick, Armin W. Knoll, Teddie Peregrino Magbitang, Robert Dennis Miller, Russell Clayton Pratt, Charles-Gordon Wade. Invention is credited to Richard Anthony DiPietro, Urs T. Duerig, Jane Elizabeth Frommer, Bernd Walter Gotsmann, Erik Christopher Hagberg, James Lupton Hedrick, Armin W. Knoll, Teddie Peregrino Magbitang, Robert Dennis Miller, Russell Clayton Pratt, Charles-Gordon Wade.
United States Patent |
8,488,436 |
DiPietro , et al. |
July 16, 2013 |
High density data storage medium, method and device
Abstract
A composition of matter for the recording medium of nanometer
scale thermo-mechanical information storage devices and a nanometer
scale thermo-mechanical information storage device. The composition
includes: one or more polyaryletherketone copolymers, each of the
one or more polyaryletherketone copolymers comprising (a) a first
monomer including an aryl ether ketone and (b) a second monomer
including an aryl ether ketone and a first phenylethynyl moiety,
each of the one or more polyaryletherketone copolymers having two
terminal ends, each terminal end having a phenylethynyl moiety the
same as or different from the first phenylethynyl moiety. The one
or more polyaryletherketone copolymers are thermally cured and the
resulting cross-linked polyaryletherketone resin used as the
recording layer in an atomic force data storage device.
Inventors: |
DiPietro; Richard Anthony
(Campbell, CA), Duerig; Urs T. (Rueschlikon, CH),
Frommer; Jane Elizabeth (San Jose, CA), Gotsmann; Bernd
Walter (Horgen, CH), Hagberg; Erik Christopher
(Evansville, IN), Hedrick; James Lupton (Pleasanton, CA),
Knoll; Armin W. (Adliswil, CH), Magbitang; Teddie
Peregrino (San Jose, CA), Miller; Robert Dennis (San
Jose, CA), Pratt; Russell Clayton (Oakland, CA), Wade;
Charles-Gordon (Los Gatos, CA) |
Applicant: |
Name |
City |
State |
Country |
Type |
DiPietro; Richard Anthony
Duerig; Urs T.
Frommer; Jane Elizabeth
Gotsmann; Bernd Walter
Hagberg; Erik Christopher
Hedrick; James Lupton
Knoll; Armin W.
Magbitang; Teddie Peregrino
Miller; Robert Dennis
Pratt; Russell Clayton
Wade; Charles-Gordon |
Campbell
Rueschlikon
San Jose
Horgen
Evansville
Pleasanton
Adliswil
San Jose
San Jose
Oakland
Los Gatos |
CA
N/A
CA
N/A
IN
CA
N/A
CA
CA
CA
CA |
US
CH
US
CH
US
US
CH
US
US
US
US |
|
|
Assignee: |
International Business Machines
Corporation (Armonk, NY)
|
Family
ID: |
39583780 |
Appl.
No.: |
13/365,408 |
Filed: |
February 3, 2012 |
Prior Publication Data
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Document
Identifier |
Publication Date |
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US 20120147728 A1 |
Jun 14, 2012 |
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Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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12835811 |
Jul 14, 2010 |
8169882 |
|
|
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12051128 |
Mar 19, 2008 |
8383756 |
|
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11618940 |
Jan 2, 2007 |
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Current U.S.
Class: |
369/154;
427/271 |
Current CPC
Class: |
C08G
65/46 (20130101); G11B 11/007 (20130101); C08G
65/4012 (20130101); B82Y 10/00 (20130101); G11B
9/149 (20130101); G11B 9/1472 (20130101) |
Current International
Class: |
G11B
3/00 (20060101); B05D 3/00 (20060101); B05D
5/00 (20060101) |
Field of
Search: |
;427/271 ;369/154 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Other References
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.
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|
Primary Examiner: Heincer; Liam
Attorney, Agent or Firm: Schmeiser, Olsen & Watts
Parent Case Text
This application is division of U.S. patent application Ser. No.
12/835,811 filed on Jul. 14, 2010 now U.S. Pat. No. 8,169,882 which
is a division of U.S. patent application Ser. No. 12/051,128 filed
Mar. 19, 2008 now U.S. Pat. No. 8,383,756 which is a continuation
of U.S. patent application Ser. No. 11/618,940 filed on Jan. 2,
2007, now abandoned.
Claims
What is claimed is:
1. A data storage device, comprising: a recording medium comprising
a layer of polyaryletherketone resin overlying a substrate, in
which topographical states of said layer of said
polyaryletherketone resin represent data, said polyaryletherketone
resin comprising a thermally cured mixture of one or more
polyaryletherketone copolymers, each of said one or more
polyaryletherketone copolymers independently comprising a first
monomer, a second monomer, a first terminal end and a second
terminal end, the first monomer including an aryl ether ketone, the
second monomer including a first phenylethynyl moiety, the first
terminal end including a second phenylethynyl moiety and the second
terminal end including a third phenylethynyl moiety; a head having
one or more thermo-mechanical probes, each of said one or more
thermo-mechanical probes including a resistive region for locally
heating a tip of said thermo-mechanical probe in response to
electrical current being applied to said one or more
thermo-mechanical probes; and a scanning system for scanning said
head across a surface of said recording medium.
2. The data storage device of claim 1, wherein each
polyaryletherketone copolymer of said one or more
polyaryletherketone copolymers includes: (i) m repeat units
represented by the structure --R.sup.1--O--R.sup.2--O--
interspersed with n repeat units represented by the structure
--R.sup.1--O--R.sup.3--O--, and terminated by a first terminal
group represented by the structure R.sup.4--O-- and a second
terminal group represented by the structure --R.sup.1--O--R.sup.4,
or (ii) m repeat units represented by the structure
--R.sup.1--O--R.sup.2--O-- interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.5--O--, and
terminated by a first terminal group represented by the structure
R.sup.4--O-- and a second terminal group represented by the
structure --R.sup.1--O--R.sup.4, or (iii) m repeat units
represented by the structure --R.sup.1--O--R.sup.2--O--
interspersed with n repeat units represented by the structure
--R.sup.1--O--R.sup.3--O--, terminated by a first terminal group
represented by the structure R.sup.6--O-- and a second terminal
group represented by the structure --R.sup.1--O--R.sup.6, or (iv) m
repeat units represented by the structure
--R.sup.1--O--R.sup.2--O-- interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.5--O--, a first
terminal group represented by the structure R.sup.6--O-- and a
second terminal group represented by the structure
--R.sup.1--O--R.sup.6; wherein O=oxygen, and occurs as a link
between all R groups; wherein R.sup.1 is ##STR00010## wherein
R.sup.2 is selected from the group consisting of: ##STR00011##
wherein R.sup.3 is selected from the group consisting of
##STR00012## wherein R.sup.4 is selected from the group consisting
of ##STR00013## wherein R.sup.5 is selected from the group
consisting of ##STR00014## wherein R.sup.6 is selected from the
group consisting of ##STR00015## and wherein m is an integer of 2
or more, n is an integer of 1 or more, m is greater than n and m+n
is from about 5 to about 50.
3. The data storage device of claim 2, wherein, in structures (i),
(ii), (iii) and (iv) said m repeat units and said n repeat units
are randomly interspersed.
4. The data storage device of claim 1, further including: a heat
control circuit for independently applying said electrical current
to each of said one or more thermo-mechanical probes; a write
control circuit for independently controlling heating of each of
said one or more thermo-mechanical probes by said heat control
circuit to write data bits to said recording medium; an erase
control circuit for independently controlling heating of each of
said one or more thermo-mechanical probes by said heat control
circuit to erase data bits from said recording medium; and a read
control circuit for independently reading data bits from said
recording medium with each of said one or more thermo-mechanical
probes.
5. The data storage device of claim 1, further including: a contact
mechanism for contacting said recording medium with respective tips
of said one or more thermo-mechanical probes.
6. The data storage device of claim 1, wherein said layer of
polyaryletherketone resin has a thickness between about 10 nm and
about 500 nm.
7. The data storage device of claim 1, further including: a heat
control circuit for independently applying said electrical current
to each of said one or more thermo-mechanical probes; and a write
control circuit for independently controlling heating of each of
said one or more thermo-mechanical probes by said heat control
circuit to write data bits to said recording medium.
8. The device of claim 1, wherein said polyaryletherketone resin
has been cured at a temperature between about 300.degree. C. and
about 400.degree. C.
9. The device of claim 1, wherein said polyaryletherketone resin
has a glass transition temperature of between about 100.degree. C.
and about 180.degree. C.
10. The device of claim 2, wherein, in structures (i), (ii), (iii)
and (iv), a molar ratio of a first repeat unit containing R.sup.1
and R.sup.2 groups to a second repeat unit containing either
R.sup.1 and R.sup.5 groups or containing R.sup.3 and R.sup.2 groups
is greater than 1 and the ratio m/n is greater than 1.
11. The device of claim 1, wherein each of said one or more
polyaryletherketone copolymers has a molecular weight between about
3,000 Daltons and about 10,000 Daltons.
12. The device of claim 1, wherein each of said one or more
polyaryletherketone copolymers has a molecular weight between about
4,000 Daltons and about 5,000 Daltons.
13. The device of claim 1, wherein said polyaryletherketone resin
comprises polyaryletherketone ketone copolymer having the
structure: ##STR00016## wherein y is less than 1 and greater than 0
and wherein n is an integer.
14. The device of claim 1, wherein each of said one or more
polyaryletherketone copolymers includes only carbon, oxygen,
hydrogen and fluorine.
Description
FIELD OF THE INVENTION
The present invention relates to the field of high-density data
storage and read-back and more specifically to a data storage and
read-back medium, a data storage and read-back system, and a data
storage and read-back method.
BACKGROUND OF THE INVENTION
Current data storage and imaging methodologies operate in the
micron regime. In an effort to store ever more information in
ever-smaller spaces, data storage density has been increasing. In
an effort to reduce power consumption and increase the speed of
operation of integrated circuits, the lithography used to fabricate
integrated circuits is pressed toward smaller dimensions and denser
imaging. As data storage size increases and density increases and
integrated circuit densities increase, there is a developing need
for compositions of matter for the storage media that operate in
the nanometer regime.
SUMMARY OF THE INVENTION
A first aspect of the present invention is a composition of matter,
comprising: one or more polyaryletherketone copolymers, each of the
one or more polyaryletherketone copolymers comprising (a) a first
monomer including an aryl ether ketone and (b) a second monomer
including an aryl ether ketone and a first phenylethynyl moiety,
each of the one or more polyaryletherketone copolymers having two
terminal ends, each terminal end having a phenylethynyl moiety the
same as or different from the first phenylethynyl moiety.
A second aspect of the present invention is a method, forming a
layer of polyaryletherketone resin by applying a layer of one or
more polyaryletherketone copolymers and thermally curing the layer
of one or more polyaryletherketone copolymers, each of the one or
more polyaryletherketone copolymers comprising (a) a first monomer
including an aryl ether ketone and (b) a second monomer including
an aryl ether ketone and a first phenylethynyl moiety, each of the
one or more polyaryletherketone copolymers having two terminal
ends, each terminal end having a phenylethynyl moiety the same as
or different from the first phenylethynyl moiety, and bringing a
thermal-mechanical probe heated to a temperature of greater than
about 100.degree. C. into proximity with the layer of a
polyaryletherketone resin multiple times to induce deformed regions
at points in the layer of the polyaryletherketone resin, the
polyaryletherketone resin the thermal mechanical probe heating the
points in the layer of the resin and thereby writing information in
the layer of the resin.
A third aspect of the present invention is a data storage device,
comprising: a recording medium comprising a layer of
polyaryletherketone resin overlying a substrate, in which
topographical states of the layer of the polyaryletherketone resin
represent data, the polyaryletherketone resin comprising thermally
cured one or more polyaryletherketone copolymers, each of the one
or more polyaryletherketone copolymers comprising (a) a first
monomer including an aryl ether ketone and (b) a second monomer
including an aryl ether ketone and a first phenylethynyl moiety,
each of the one or more polyaryletherketone copolymers having two
terminal ends, each terminal end having a phenylethynyl moiety the
same as or different from the first phenylethynyl moiety; a
read-write head having one or more thermo-mechanical probes, each
of the one or more thermo-mechanical probes including a resistive
region for locally heating a tip of the thermo-mechanical probe in
response to electrical current being applied to the one or more
thermo-mechanical probes; and a scanning system for scanning the
read-write head across a surface of the recording medium.
BRIEF DESCRIPTION OF DRAWINGS
The features of the invention are set forth in the appended claims.
The invention itself, however, will be best understood by reference
to the following detailed description of an illustrative embodiment
when read in conjunction with the accompanying drawings,
wherein:
FIGS. 1A through 1C illustrate the structure and operation of a tip
assembly for a data storage device including the data storage
medium according to the embodiments of the present invention;
and
FIG. 2 is an isometric view of a local probe storage array
including the data storage medium according to the embodiments of
the present invention; and
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1A through 1C illustrate the structure and operation of a tip
assembly 100 for a data storage device including the data storage
medium according to the embodiments of the present invention. In
FIG. 1A, probe tip assembly 100 includes a U-shaped cantilever 105
having flexible members 105A and 105B connected to a support
structure 110. Flexing of members 105A and 105B provides for
substantial pivotal motion of cantilever 105 about a pivot axis
115. Cantilever 105 includes an indenter tip 120 fixed to a heater
125 connected between flexing members 105A and 105B. Flexing
members 105A and 105B and heater 125 are electrically conductive
and connected to wires (not shown) in support structure 110. In one
example, flexing members 105A and 105B and indenter tip 120 are
formed of highly-doped silicon and have a low electrical
resistance, and heater 125 is formed of lightly doped silicon
having a high electrical resistance sufficient to heat indenter tip
120, in one example, to between about 100.degree. C. and about
500.degree. C. when current is passed through heater 125. The
electrical resistance of heater 125 is a function of
temperature.
Also illustrated in FIG. 1A is a storage medium (or a recording
medium) 130 comprising a substrate 130A, and a cured
polyaryletherketone resin layer 130B. In one example, substrate
130A comprises silicon. In one example, curing is performed at a
temperature between about 300.degree. C. and about 400.degree. C.
Cured polyaryletherketone resin layer 130B may be formed by
solution coating, spin coating, dip coating or meniscus coating
polyaryletherketone copolymer and reactive diluent formulations and
performing a curing operation on the resultant coating. In one
example, cured polyaryletherketone resin layer 130B has a thickness
between about 10 nm and about 500 nm. The composition of cured
polyaryletherketone resin layer 130B is described infra. An
optional penetration stop layer 130C is shown between cured
polyaryletherketone resin layer 130B and substrate 130A.
Penetration stop layer 130C limits the depth of penetration of
indenter tip 120 into cured polyaryletherketone resin layer
130B.
Turning to the operation of tip assembly 100, in FIG. 1A, an
indentation 135 is formed in cured polyaryletherketone resin layer
130B by heating indenter tip 120 to a writing temperature T.sub.W
by passing a current through cantilever 105 and pressing indenter
tip 120 into cured polyaryletherketone resin layer 130B. Heating
indenter tip 120 allows the tip to penetrate the cured
polyaryletherketone resin layer 130B forming indentation 135, which
remains after the tip is removed. In a first example, the cured
polyaryletherketone resin layer 130B is heated by heated indenter
tip 120, the temperature of the indenter tip being not greater than
about 500.degree. C., to form indentation 135. In a second example,
the cured polyaryletherketone resin layer 130B is heated by heated
indenter tip 120, the temperature of the indenter tip being not
greater than about 400.degree. C., to form indentation 135. In a
third example, the cured polyaryletherketone resin layer 130B is
heated by heated indenter tip 120, the temperature of the indenter
tip being between about 200.degree. C. and about 500.degree. C., to
form indentation 135. In a fourth example, the cured
polyaryletherketone resin layer 130B is heated by heated indenter
tip 120, the temperature of the indenter tip being between about
100.degree. C. and about 400.degree. C., to form indentation 135.
As indentations 135 are formed, a ring 135A of cured
polyaryletherketone resin is formed around the indentation.
Indentation 135 represents a data bit value of "1", a data bit
value of "0" being represented by an absence of an indentation.
Indentations 135 are nano-scale indentations (several to several
hundred nanometers in width).
FIGS. 1B and 1C illustrate reading the bit value. In FIGS. 1B and
1C, tip assembly 100 is scanned across a portion of cured
polyaryletherketone resin layer 130B. When indenter tip 120 is over
a region of cured polyaryletherketone resin layer 130B not
containing an indentation, heater 125 is a distance D1 from the
surface of the cured polyaryletherketone resin layer (see FIG. 1B).
When indenter tip 120 is over a region of cured polyaryletherketone
resin layer 130B containing an indentation, heater 125 is a
distance D2 from the surface of the cured polyaryletherketone resin
layer (see FIG. 1C) because the tip "falls" into the indentation.
D1 is greater than D2. If heater 125 is at a temperature T.sub.R
(read temperature), which is lower than T.sub.W (write
temperature), there is more heat loss to substrate 130A when
indenter tip 120 is in an indentation than when the tip is not.
This can be measured as a change in resistance of the heater at
constant current, thus "reading" the data bit value. It is
advantageous to use a separate heater for reading, which is
mechanically coupled to the tip but thermally isolated from the
tip. A typical embodiment is disclosed in Patent Application EP
05405018.2, 13 Jan. 2005.
"Erasing" (not shown) is accomplished by positioning indenter tip
120 in close proximity to indentation 135, heating the tip to a
temperature T.sub.E (erase temperature), and applying a loading
force similar to writing, which causes the previously written
indent to relax to a flat state whereas a new indent is written
slightly displaced with respect to the erased indent. The cycle is
repeated as needed for erasing a stream of bits whereby an indent
always remains at the end of the erase track. T.sub.E is typically
greater than T.sub.W. The erase pitch is typically on the order of
the rim radius. In a first example, the cured polyaryletherketone
resin layer 130B is heated by heated indenter tip 120, the
temperature of the indenter tip is not greater than about
500.degree. C., and the erase pitch is 10 nm to eliminate
indentation 135. In a second example, the cured polyaryletherketone
resin layer 130B is heated by heated indenter tip 120, the
temperature of the indenter tip is not greater than about
400.degree. C., and the erase pitch is 10 nm to eliminate
indentation 135. In a third example, the cured polyaryletherketone
resin layer 130B is heated by heated indenter tip 120, the
temperature of the indenter tip is between about 200.degree. C. and
about 400.degree. C., and the erase pitch is 10 nm to eliminate
indentation 135. In a fourth example, the cured polyaryletherketone
resin layer 130B is heated by heated indenter tip 120, the
temperature of the indenter tip is between about 200.degree. C. and
about 500.degree. C., and the erase pitch is 10 nm to eliminate
indentation 135.
FIG. 2 is an isometric view of a local probe storage array 140
including the data storage medium according to the embodiments of
the present invention. In FIG. 2, local probe storage array 140
includes substrate 145 having a cured polyaryletherketone resin
layer 150 (similar to cured polyaryletherketone resin layer 130B of
FIGS. 1A, 1B and 1C), which acts as the data-recording layer. An
optional tip penetration stop layer may be formed between cured
polyaryletherketone resin layer 150 and substrate 145. In one
example, substrate 145 comprises silicon. Cured polyaryletherketone
resin layer 150 may be formed by solution coating, spin coating,
dip coating or meniscus coating uncured polyaryletherketone resin
formulations and performing a curing operation on the resultant
coating. In one example, cured polyaryletherketone resin layer 150
has a thickness between about 10 nm and about 500 nm and a root
mean square surface roughness across a writeable region of cured
polyaryletherketone resin layer 150 of less than about 1.0 nm
across the cured polyaryletherketone resin layer. The composition
of cured polyaryletherketone resin layer 150 is described infra.
Positioned over cured polyaryletherketone resin layer 150 is a
probe assembly 155 including an array of probe tip assemblies 100
(described supra). Probe assembly 155 may be moved in the X, Y and
Z directions relative to substrate 145 and cured
polyaryletherketone resin layer 150 by any number of devices as is
known in the art. Switching arrays 160A and 160B are connected to
respective rows (X-direction) and columns (Y-direction) of probe
tip assemblies 100 in order to allow addressing of individual probe
tip assemblies. Switching arrays 160A and 160B are connected to a
controller 165 which includes a write control circuit for
independently writing data bits with each probe tip assembly 100, a
read control circuit for independently reading data bits with each
probe tip assembly 100, an erase control circuit for independently
erasing data bits with each probe tip assembly 100, a heat control
circuit for independently controlling each heater of each of the
probe tip assembles 100, and X, Y and Z control circuits for
controlling the X, Y and Z movement of probe assembly 155. The Z
control circuit controls a contact mechanism (not shown) for
contacting the cured polyaryletherketone resin layer 150 with the
tips of the array of probe tip assemblies 100.
During a write operation, probe assembly 155 is brought into
proximity to cured polyaryletherketone resin layer 150 and probe
tip assemblies 100 are scanned relative to the cured
polyaryletherketone resin layer. Local indentations 135 are formed
as described supra. Each of the probe tip assemblies 100 writes
only in a corresponding region 170 of cured polyaryletherketone
resin layer 150. This reduces the amount of travel and thus time
required for writing data.
During a read operation, probe assembly 155 is brought into
proximity to cured polyaryletherketone resin layer 150 and probe
tip assemblies 100 are scanned relative to the cured
polyaryletherketone resin layer. Local indentations 135 are
detected as described supra. Each of the probe tip assemblies 100
reads only in a corresponding region 170 of cured
polyaryletherketone resin layer 150. This reduces the amount of
travel and thus the time required for reading data.
During an erase operation, probe assembly 155 is brought into
proximity to cured polyaryletherketone resin layer 150, and probe
tip assemblies 100 are scanned relative to the cured
polyaryletherketone resin layer. Local indentations 135 are erased
as described supra. Each of the probe tip assemblies 100 erases
only in a corresponding region 170 of cured polyaryletherketone
resin layer 150. This reduces the amount of travel and thus time
required for erasing data.
Additional details relating to data storage devices described supra
may be found in the articles "The Millipede--More than one thousand
tips for future AFM data storage," P. Vettiger et al., IBM Journal
of Research and Development. Vol. 44 No. 3, May 2000 and "The
Millipede--Nanotechnology Entering Data Storage," P. Vettiger et
al., IEEE Transaction on Nanotechnology, Vol. 1, No, 1, March 2002.
See also United States Patent Publication 2005/0047307, Published
Mar. 3, 2005 to Frommer et al. and United States Patent Publication
2005/0050258, Published Mar. 3, 2005 to Frommer et al., both of
which are hereby included by reference in their entireties.
Turning to the composition of cured polyaryletherketone resin layer
130B of FIGS. 1A through 1C. It should be understood that for the
purposes of the present invention curing a polymer implies
cross-linking the polymer to form a cross-linked polymer or
resin.
The polyaryletherketone resin medium or imaging layer of the
embodiments of the present invention advantageously meets certain
criteria. These criteria include high thermal stability to
withstand millions of write and erase events, low wear properties
(little or no pickup of material by tips), low abrasion (tips do
not easily wear out), low viscosity for writing, glassy character
with no secondary relaxations for long data bit lifetime, and shape
memory for erasability.
Cured polyaryletherketone resins according to embodiments of the
present invention have high temperature stability while maintaining
a low glass transition temperature (Tg). In a first example, cured
polyaryletherketone resins according to embodiments of the present
invention have a Tg of less than about 180.degree. C. In a second
example, cured polyaryletherketone resins according to embodiments
of the present invention have a Tg of between about 100.degree. C.
and about 180.degree. C.
The glass transition temperature should be adjusted for good write
performance. To optimize the efficiency of the write process there
should be a sharp transition from the glassy state to the rubbery
state. A sharp transition allows the cured resin to flow easily
when a hot tip is brought into contact and quickly return to the
glassy state once the hot tip is removed. However, too high a
T.sub.g leads to high write currents and damage to the probe tip
assemblies described supra.
A formulation of polyaryletherketone copolymer according to
embodiments of the present invention comprises one or more
polyaryletherketone copolymers, each polyaryletherketone copolymer
of the one or more polyaryletherketone copolymers having the
structure:
(i) m repeat units represented by the structure
--R.sup.1--O--R.sup.2--O-- interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.3--O--, and
terminated by a first terminal group represented by the structure
R.sup.4--O-- and a second terminal group represented by the
structure --R.sup.1--O--R.sup.4, or
(ii) m repeat units represented by the structure
--R.sup.1--O--R.sup.2--O-- interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.5--O--, and
terminated by a first terminal group represented by the structure
R.sup.4--O-- and a second terminal group represented by the
structure --R.sup.1--O--R.sup.4, or
(iii) m repeat units represented by the structure
--R.sup.1--O--R.sup.2--O-- interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.3--O--, terminated
by a first terminal group represented by the structure R.sup.6--O--
and a second terminal group represented by the structure
--R.sup.1--O--R.sup.6, or
(iv) m repeat units represented by the structure
--R.sup.1--O--R.sup.2--O--interspersed with n repeat units
represented by the structure --R.sup.1--O--R.sup.5--O--, a first
terminal group represented by the structure R.sup.6--O-- and a
second terminal group represented by the structure
--R.sup.1--O--R.sup.6;
wherein O=oxygen, and occurs as a link between all R groups;
wherein R.sup.1 is selected from the group consisting of:
##STR00001##
wherein R.sup.2 is selected from the group consisting of:
##STR00002##
wherein R.sup.3 is selected from the group consisting of
mono(arylacetylenes), mono(phenylethynyls),
##STR00003##
wherein R.sup.4 is selected from the group consisting of
mono(arylacetylenes), mono(phenylethynyls),
##STR00004##
wherein R.sup.5 is selected from the group consisting of
mono(arylacetylenes), mono(phenylethynyls),
##STR00005##
wherein R.sup.6 is selected from the group consisting of
mono(arylacetylenes), mono(phenylethynyls),
##STR00006## and
wherein m is an integer of 2 or more, n is an integer of 1 or more,
m is greater than n and m+n is from about 5 to about 50.
The molar ratio of a first repeat unit (containing R.sup.1 and
R.sup.2 groups) to a second repeat unit (containing either R.sup.1
and R.sup.5 groups or R.sup.3 and R.sup.2 groups) in structures
(i), (ii), (iii) and (iv) is kept greater than 1, therefore the
ratio m/n is greater than 1. The acetylene moieties in the R.sup.3,
R.sup.4, R.sup.5, and R.sup.6 groups, whichever are present, react
during thermal curing with each other to cross-link the
polyaryletherketone copolymers into a polyaryletherketone resin by
cyclo-addition.
In a first example, polyaryletherketone copolymers according to
embodiments of the present invention advantageously have a
molecular weight between about 3,000 Daltons and about 10,000
Daltons. In a second example, polyaryletherketone copolymers
according to embodiments of the present invention advantageously
have a molecular weight between about 4,000 Daltons and about 5,000
Daltons.
SYNTHESIS EXAMPLES
All materials were purchased from Aldrich and used without further
purification unless otherwise noted.
Synthesis of the reactive endgroup 3-(phenylethynyl)phenol
(Structure XV):
##STR00007##
3-Iodophenol (5.00 gram, 22.7 mmol),
bis(triphenylphospine)palladium(II) dichloride
(PdCl.sub.2(PPh.sub.3).sub.2) (160 mg), triphenylphospine
(PPh.sub.3) (420 mg), and CuI (220 mg) were suspended in
triethylamine (NEt.sub.3) (150 mL) under an N.sub.2 atmosphere.
Phenylacetylene (3.1 mL, 2.9 gram, 28.4 mmol, 1.25 eq) was added by
syringe. The reaction mixture was then stirred and heated to
70.degree. C. using an oil bath for 38 hours. Excess NEt.sub.3 was
removed under reduced pressure. The remaining solids were extracted
with 3.times.50 mL diethyl ether, which was then filtered and
evaporated. The crude product was purified by column chromatography
(silica, 3:1 hexanes-ethyl acetate) to give 4.1 gram of an orange
solid. Further purification was accomplished by sublimation
(100.degree. C., 28 mTorr) to give 3-(phenylethynyl)phenol as a
white solid (3.3 g, 75% yield).
Synthesis of the reactive cross-linking group
3,3'-dihydroxydiphenylacetylene (Structure XVII):
##STR00008##
To a suspension of 3-iodophenol (3.73 gram, 17 mmol),
PdCl.sub.2(PPh.sub.3).sub.2 (120 mg), CuI (161 mg), and PPh.sub.3
(333 mg) in NEt.sub.3 (100 mL) under N.sub.2 was added a solution
of 3-hydroxyphenylacetylene (2.00 gram, 17 mmol) in NEt.sub.3 (10
mL). The mixture was stirred and heated to 70.degree. C. using an
oil bath for 18 h. Excess NEt.sub.3 was removed under reduced
pressure, and the remaining solids were extracted with 4.times.50
mL diethyl ether which was then filtered and evaporated. The crude
product was purified by suspending in 80 mL CH.sub.2Cl.sub.2,
stirring for 1 hour, and filtering to give the final product as a
yellow powder (2.96 g, 83% yield).
Synthesis of a polyaryletherketone copolymer (Structure XXI):
##STR00009##
In a multi-necked flask equipped with a mechanical stiffing
apparatus and a Dean-Stark trap, 4,4'-difluorobenzophenone (1.4187
gram, 6.502 mmol), resorcinol (0.5326 g, 4.838 mmol),
3,3'-dihydroxydiphenylacetylene (0.2540 g, 1.209 mmol),
3-hydroxydiphenylacetylene (0.1753 g, 0.9037 mmol), and potassium
carbonate (3 g, 22 mmol) were suspended in a mixture of
dimethylformamide (DMF) (10 mL) and toluene (20 mL). The reaction
mixture was vigorously stirred and heated to 130.degree. C. for 16
hours under a slow flow of dry nitrogen, and toluene was removed
periodically via the Dean-Stark trap. At the end of the 16 h
period, the temperature was increased to 150.degree. C. for another
8 hours. The reaction was then cooled and the polymer was isolated
by multiple precipitations using THF and methanol. Molecular
weights were adjusted by using different proportions of
(R.sup.1+R.sup.2) to (R.sup.3) and several different molecular
weight polymers were prepared.
Thus, the embodiments of the present invention provide for
compositions of matter for the storage media that operate in the
nanometer regime.
The description of the embodiments of the present invention is
given above for the understanding of the present invention. It will
be understood that the invention is not limited to the particular
embodiments described herein, but is capable of various
modifications, rearrangements and substitutions as will now become
apparent to those skilled in the art without departing from the
scope of the invention. Therefore, it is intended that the
following claims cover all such modifications and changes as fall
within the true spirit and scope of the invention.
* * * * *